Electrical control mechanism for drive means in address printing machines



p 1958 F. USSELMANN 2,853,169

. ELECTRICAL CONTROL MECHANISM FOR DRIVE MEANS IN ADDRESS PRINTING MACHINES Flled April 18, 1955 5 Sheets-Sheet 1 Sept. 23, 1958 F. USSELMANN ELECTRICAL CONTROL MECHANISM FOR DRIVE MEANS IN ADDRESS PRINTING MACHINES Filed April 18, 1955 I5 Sheets-Sheet 2 Sept. 23, 1958 FiledApril 18, 1955 F. USSELMANN ELECTRICAL CONTROL MECHANISM F0 RI MEANS IN ADDRESS PRINTING MAC ES 3 Sheets-Sheet United States Patent ELECTRICAL CONTROL MECHANISM FOR DRHE MEANS IN ADDRESS PRINTING MACHINES Fernand Usselmann, Sceaux, France Application April 18, 1955, Serial No. 502,086

Claims priority, application France April 24, 1954 13 Claims. (Cl. 192-1165) This invention relates to electrical control mechanism which is intended for use in a case Where two or more shafts must be driven by a common drive shaft in a certain relative angular position.

The object of this invention is to provide. a control mechanism by which when the drive connection to one or other or both of the driven shafts has been interrupted, drive will be re-established automatically with the driven shafts in the proper angular relationship.

Such a problem arises, for example, in addressing machines which all comprise two principal mechanisms, one the mechanism for the feed of the address-plates and the other the printing mechanism: it is necessary to actuate one or the other of these mechanisms or both together, in order to be able to bring about the following opera tions:

(a) Feed without printing either to bring the first plate into the printing position, or to carry out a visual or automatic selection of the address-plates.

(b) Printing without feed in order to effect a repetition of the address for example (0) Printing and feed in order to print a series of successive addresses.

It is necessary, in order to obtain correct functioning of the addressing machine, that the shafts of the feed and printing mechanisms shall be situated in the same relative angular position every time.

The invention is concerned with cases in which the problem of maintaining two or more driven parts receiving drive from a driving shaft in a certain angular relationship arises.

The main object of this invention is to provide a control arrangement by which such operating conditions as those referred to can be automatically obtained.

In carrying out the invention an electro-magnetically controlled coupling between a driven shaft and the driving shaft is effective for a number of defined positions on the driving shaft.

The arrangement comprises also a locking device capable of holding the coupling in a disengaged position so long as the locking device is not released, the release of the locking device permitting coupling to take place under the action of an electrical impulse delivered to a control electro-magnet.

In addition, the driven shaft comprises means to return the locking device to the locking position.

The mechanism comprises two or more driven shafts each provided with such an electro-magnetically controlled coupling and for simultaneous coupling to the driven shafts the closure of the feed circuit of each of the electro-magnets is efiected in a permitted zone such that the circuit is broken before and after the. theoretical engagement point for each defined engagement position of each driven shaft; the permitted zone provides a margin sufficient to take into account the mechanical and electrical characteristics of the wholeof the mechanism while still ensuring that the drive is effected for the first defined pngagement position.

2,853,169 Patented Sept. 23, 1958 For successive couplings, the closure of the circuit of each electro-magnet controlling the engagement is permitted once only per revolution in the permitted zone preceding the theoretical engagement point.

More particularly the drive shaft can drive a switch control member which ensures the closure of a switch for each defined engagement position in the permitted zone, while each driven shaft drives a switch control member which ensures the closure of a switch in a zone which, when the drive and driven shafts are in the required angular synchronism, covers at least a part of the permitted zone and extends beyond the theoretical engagement point by a distance sufficient to ensure contact when the mechanism is disengaged, without covering the neighbouring permitted zone, the afore-mentioned switches being disposed in series in relation to each electro-magnet controlling the engagement of the coupling.

Asapplied to an addressing machine, the two shafts concerned would be the plate feed shaft and a printing shaft, these shafts being capable of being driven, either separately or simultaneously, by a common drive shaft each, through the intermediary of a coupling device of this invention. Such an application is shown in the accompanying drawings.

Other features and advantages of the present invention will appear from the description which will follow with reference to the accompanying drawings which show by way of example one embodiment of the present invention.

In these drawings:

Figure 1 is a cross-section .of a couplingvbetween a drive shaft and a driven shaft;

Figure 2 is a section on the line 11-11, Figure 1;

Figure 3 is a section similar to Figure 2, but applied to a mechanism comprising a drive shaft and two driven shafts;-

Figure 4 is a circuit diagram capable of being used for the control of the mechanism represented in Figure 3;

Figure 5 is a section on the line VV, Figure 3, and Figure 6 is a diagram showing the closing time of the contacts effecting the closure of the engagement-control electro-magnets.

Referring to Figure l, the coupling device according to the invention is provided to enable driven shaft 1 to be driven by a drive shaft 2. The latter is driven, for ex-' ample by means of a pulley 3 and a belt (not shown), by a motor (not shown) such as an electric motor.

On the drive shaft 2 is keyed a pinion 4 meshing with a toothed wheel 5 loose on the driven shaft 1. A ratchet wheel 6 is secured to the wheel 5, the ratchet having for example four teeth which can engage a pawl 7 carried by a plate, 8.

The pawl 7 is normally held out of engagement by a latch 9, which is drawn into the withdrawn position by a spring 14 but is held in the engaging or locking position by a small pawl 11. This pawl 11, which can pivot about a pin 12, is drawn by a spring 13 towards the lockmg position. One of the, arms of the pawl 11 either constitutes the armature of an electro-magnet 14, as is shown, oris connected mechanically to the armature.

The plate 8 has a part 15 which forms a cam upon which bears the end of one. arm of a bell-crank lever 16 urged by a spring l7 against the cam plate. The end of the other arm of the bell-crank lever 16 carries a stop 18 against which can bear a pin 19 carried by the latch 9 when the latter moves into the withdrawn position.

The operation of the coupling device which has been described is as follows:

In the rest position, the latch 9 is retained by the pawl 11 in. the locking position, the pawl 7 bearing on the latch 9.

' To efifect engagement, a momentary electrical impulse is transmitted to the electromagnet 14. The armature ice of the electro-magnet is moved so that pawl 11 turns in a counter-clockwise direction and frees the latch 9 which is drawn into the withdrawn position by its spring 10. The pawl 7 is thus freed and swings into engagement with the first of the teeth of ratchet wheel 6 to pass. The driven shaft 1 is thus driven.

At the same time, the pin 19 of the latch 9 has moved into contact with the stop 18 on the lever 16, so that when the cam 15 rides over the end of the bell-crank lever 1-6 and turns it in a clockwise direction, the stop 18 returns the latch 9 into the locking position against the action of the spring 10.

The action of the electro-magnet 14 having ceased, the pawl 11 again retains the latch 9 in the locking position. Under these conditions, the pawl 7 again encounters the bolt after one revolution of the driven shaft 1 so that the pawl '7 is disengaged from the ratchet wheel 6. The coupling between the driving shaft 2 and the driven shaft 1 is thus broken and the shaft 1 is stopped.

In order to maintain the driven shaft 1 in the stopped position there is provided a counter-pawl 2% (shown in Figure 5) which opposes rotational movement in the opposite direction: rotational movement in the normal direction is prevented by a stop 21 against which the pawl 7 bears.

In order to cause the driven shaft 1 to make several revolutions without disengagement, it is sufficient either to maintain the circuit of the electro-magnet 314 closed, or to close this circuit momentarily before each movement of the pawl 7 to the latch 9 so as to cause the latter to move aside in time from the path of the pawl 7.

Provision is made to enable two or more mechanisms to receive their movement from one and the same driving shaft through the intermediary of couplings 'which must operate in angular synchronism (i. e. without shifting) by a fraction of a revolution or even a complete revolution, either on simultaneous engagement of the whole or of a part of the mechanisms, or on succcsive engagements of mechanisms individually or in groups. This angular synchronisation is brought about in the manner which will be described with particular reference to Figures 4 and 6 which relate to the particular case of two driven shafts Which may for example be the shaft for control of the feed mechanism and the shaft for control of the printing mechanism in addressing machines.

For simultaneous engagement, the closing of the feed circuit of each of the control electro-magnets such as the electro-magnet 14 in Figure 1 is permitted in a zone (which will be referred to as the permitted zone) such that the circuit is broken before and after the theoretical engagement point at each passage of a tooth of the ratchet wheel 6in Figure 1 past this point, with a margin which while being sufiicient to take into account the mechanical and electrical characteristics of the assembly, ensures that the drive is imparted by the first tooth to pass. These permitted zones have been indicated in the diagram in Figure 6 by the segments a representing the parts of a rotation of the drive shaft where a contact in series with the electro-magnet 14 is closed, the aligned arrows a, Z1, b representing the theoretical point of engagemeut.

For the successive engagements, the closing of the circuits of th electro-magnets such as 14 is permitted once only per revolution in the permitted zone as defined above, preceding the theoretical engagement point. As is seen from Figure 6, the drive shaft for the ratchet wheel 6 establishes contact in the permitted zone defined above by the segments (1.

Furthermore, each driven shaft also establishes a contact over a part of a revolution of the driven shaft as represented by the segment b in Figure 6, this part of a revolution being such that, when the drive shaft and the driven shaft are in angular synchronism, the angular zone corresponding to the segment 11 covers at least part of the angular zone corresponding to the segment a and extends beyond the theoretical engagement point (ab) by a distance sufficient to ensure contact when the mechanism is disengaged, without however covering the angular permitted zone corresponding to the adjoining segment a.

These two conditions are fulfilled due to the electrical control shown in the diagram of Figure 4. I

As is seen, the drive shaft 2 closes by means which will be described hereinafter, a switch 21 in the perm1t ted zone defined by the segments a in the diagram according to Figure 6.

Each driven shaft 1 and 1a closes a switch 22 or 22a in angular zones defined by the segments b in this same diagram, these angular zones being as is seen in Frgure 6 such that when the drive shaft and the driven shaft 1 or iii are in angular synchronism, it covers all or part of the corresponding permitted zone a and extends beyond the theoretical engagement point by a distance sufficient to ensure contact when the corresponding mechanism is disengaged without extending into the following permitted zone.

The switches 21, 22 and 22:: are connected in series with a main or master control switch 23 for the electromagnets 14 and 140, which master switch can be closed by a pedal 24. Each electro-magnet can be connected or isolated by a switch 25 or 25a.

26 indicates a main switch and 27 indicates a motor driving the drive shaft 2 by means of the pulley 3 (as shown in Figures 1 and 2).

The operation of the electrical arrangement is as follows:

in the case where simultaneous engagement of the coupling mechanisms of the two driven shafts 1 and 1a is required, the electro-magnets 14 and 14a are connected in circuit by the switches 25 and 25a.

After the closing of the master switch 23, the switches 22 and connected to the driven shafts 1 and 1a themselves being closed in the disengaged position, the feed circuit will be closed by the closing of the switch 2i controlled by the drive shaft 2 and the two mechanisms will connect simultaneously.

in the case of successive engagements i. e. when one of the two mechanisms is already in continuous movement, the master switch 23 being permanently closed.

In order to actuate that one of the mechanisms which is at rest, it is sufficient to close its switch 25 or 25a. The feed circuit of the corresponding electro-magnet 14 or 14a of the said mechanism will now be closed when the switch 21 operated by the drive shaft 2 and the switch 22 or 22a operated by the corresponding driven shaft 1 or 1a are closed simultaneously. The closure of the circuit will necessarily occur in the permitted zone preceding the theoretical engagement point (see the diagram in Figure 6) and the angular synchronism will be ensured.

The closure of the switches 21, 22 and 22a takes place in the following manner (see Figures 3 and 5):

The switch 21 is closed by a cam 28 fast with a toothed wheel 29 meshing with a pinion 30 secured to the shaft of the pulley 3 driven by the motor 27.

The switch 22 (as is seen in Figure 5) is closed by a cam 31 fast with a toothed wheel 32 meshing with a toothed wheel 33 secured to the driven shaft l.

The switch 22a would be closed in the same manner as has been shown for the switch 22 by the movement of the driven shaft 1a driving a pinion 3312 (see Figure 3) similar to pinion 33 and acting in the same manner.

The electro-magnetic coupling device of this invention is applicable especially, although not exclusively, to addressing machines which comprise a feed mechanism for the address-plates and a printing mechanism.

As is known, in addressing machines a table is provided above which there are placed the two slideways in which the address-plates move. These are piled in a feed magazine. A shuttle, to which a reciprocating movement is imparted, pushes the address-plates one by one into .the slideways .and causes them to pass over the.

passing from. the slideways the" address-plates. are. piled in a reception magazine.

The printing head is mounted on a transverse rocking shaft supported by a bearing at each end.. These "bearings are spaced so as to provide the necessary width for the passage of the documents below the'printing head. A transverse bridge, similarly of corresponding,width; serves as support to one or more intermediate. bearings for the rocking shaft. It can also: carry the inking, listing, selecting, ejecting, counting, etcL, devices. The bridge and the end bearings can .bein one single piece or composed of assembled or unassembled elements.:.

in the application of the invention to such a machine the control shafts l and 1a are employed for the printing and feed mechanisms for the address-plates and these shafts are placed under the table on eithensid'e' of a drive wheel 34' (as is shown in Figures 3 and 5), which can, in order to simplify construction, rotate freely with the ratchet wheels 6 and 6a, withwhich itis fast,-onv

the shaft 1 or the shaft 1a, this drive wheel'driving. these shafts by means of synchronised couplings as have been.

described. These shafts are. carriedby bearings 35 and 35a fixed under the table indicated at T and are connected respectively to the printing head and the shuttle by any convenient method such as eccentrics, .cams or crank-plates, connecting rods, levers andshafts.

Thus a cam (not shown) placed on the control'shaft of the printing mechanism can beiprovided to causethe. lifting of a counter-pressure part'at each descent of the printing head in order to bringthe documentiagainst the address-plate. This counterpart. can comprise. an elastic compensating device permitting the printing of documents of greatly difiering thicknesses, or documents piled under the printinghead, the document placed on the.

upper part being withdrawn. after each impression. The drive wheel 34 is driven by the electric motor 27 by means of pulleys. and gears giving the appropriate transmission ratio. are keyed in the same angular position, the drive wheel 35 5 being placed between the two. ratchet.wheels 6 and 6a.

The connection between the drive wheel 34' and the ratchet wheels can be either rigid or elastic or frictional if it is necessary to absorb the shock at the moment of engagement, the ratchet wheels always being secured in the same angular position.

The switch control. parts 30,29,'28 and 21 positively connected with the ratchet wheels, operate in the safety zones. a defined previously with referenceto the diagram of Figure 6. If the connection between the'drive wheel 5 and the ratchet wheels 6 and 6a is. rigid, the control of the switch can be taken, as represented, from the shaft carrying the control pinion 4 of thedrive wheels. A plurality of switches 21 in parallel, controlled byjcams similar to cam 28 and suitablydisposed, canbe used to diminish their frequency of operatiomtheessential being to obtain a contact in the permitted zones between each passage of the teeth of the ratchet wheel 6 or 6a.-

For each of the two driven shafts 1 and 1a there is the switch control parts 33, 32,- 31 andZZestabIis'hing contact in, the angular zone b defined with reference to the diagram in Figure 6. The addressing machine is controlled by means of the pedal 24 closingtheswitch (see Figure 4) in the pressed-down position and open- The control ratchet wheels. 6 and 6a.

in it in the rest position. This switch is placed in the feed circuit of the e-lectro-magnets 14 and 14a for controlling the feed ofthe address-plates and for the printing.

The machine has a control panel which carries theoperating switches: the master switch 26 feedingth'e motor 27 and the circuits of the electro-magnets. 14 and 14acontrolling' the engagements and the. two switches 25 and 25a respectivelyfor the circuits of the electropositionand thoprintingswitch 25iz is placed in the.

operation position. The machine is now ready to print a different address-plate 'at each cycle.

In order to print an address,-the document is placed under the printing head; the ,pedal24 pressed downdur ingv the time necessary for-the: engagement of the couplings.

ln order to pass an address-plateqwithout'printing (sight 'selection), the printing-switch 25ais placed in the. stop position-before the'pedal24'is pressed down. In

order-to print the same address-plate a number of times (repetition), the feedswitchfor the addresssplates, 25; I

is placed in the stop position before the pedal 24' is pressed down.

With the mechanismwhichhas been described it is possible to eifechin a simple manner, the'ditferent operations desirable in anaddressing'machine', especially the following operations:

(1) Automatic positive or negative selection,

(2) Automatic repetition,

(3) Continuousoperation,

(4) Automatic stopping'at' each selected impression,

(5) Automatic stopping after a predetermined number of impressions,

(6) Automatic cut-'offof continuous documents after a predetermined'number of impressions.

The'electro-magnetic control device of this invention with its angular synchronisation of .drivenshafts can be used in casesother'than that of addressing machines. It can,'for example, be applied to machines comprising more than two driven shafts (as has already been contemplated in the description given). It is sufficient to pro vide one' coupling per driven shaft-and as many. control electro-magnets as there are driven shafts, these electromagnets being arranged in parallel and each comprising a selection switch such as 25 or 25a, with as many switches" suchas 22'and'22aidisposed in series with the switch21 controlled by the drive shaft.

It is further apparent that in place of using couplings constituted by ratchet wheels and pawls it would be possible to use dog-clutch arrangements or any other devices tionbetween a rotatable driving part and at least two.

rotatable driven parts which are required to have a fixed relative 'angularposition, the combination of a drive coupling for each driven part, each coupling being arranged fordrive connection with the driving part only in defined angular positions of the driving part, an electromagnet to control each coupling part, a switch to prepare the circuit of each electromagnet, a cam driven by each driven part and formed to operate the switch in a Zone extending about the theoretical point of register of the associated driven part, and a second. switch vto complete the prepared circuit, and a cam to operate the second switch in a Zone related to a defined angular position of the driving part. I

2. In a control mechanism to establish drive connection between a rotatable driving part and at least two rotatable driven parts which are required to have a fixed relative angular position, the combination of a drive cou. plingfor eachdriventpart, eachcoupling comprising a componentmovable on its driven. part between coupling andnorncoupling position, a holding member to hold the ll coupling component in non-coupling position, an electromagnet to render the holding member inoperative to release the coupling member for coupling engagement with the driving member in one of its defined angular positions, and switches controlled by the driven parts and by the driving part to energise the associated electromagnet in zones extending about the theoretical point of angular position of the driven parts and related to the defined angular positions of the driving part.

3. In a control mechanism to establish drive connection between a rotatable driving part and at least two rotatable driven parts which are required to have a fixed relative angular position, the combination of a drive coupling for each driven part, each coupling comprising a component movable on its driven part between coupling and non-coupling position, a holding member to hold the coupling component in non-coupling position, an electromagnet to render the holding member inoperative to release the coupling member for coupling engagement with the driving member in one of its defined angular positions, switches controlled by the driven parts and by the driving part to energize the associated electromagnet in zones extending about the theoretical point of angular position of the driven parts and related to the defined angular positions of the driving part, and means operated in each rotation of a driven part to re-set the holding member.

4. In an addressing machine, in combination a driving shaft having defined drive engagement positions at which driven shafts are operatively engaged by it, at least two driven shafts capable of being selectively driven successively and simultaneously and to be maintained in angular synchronization, a positive coupling for each driven shaft, each coupling being such as to make coupling engagement between the driving shaft and a driven shaft only at one of the defined positions, electromagnets controlling the operation of each coupling, first means operated by said driving shaft for selectively energizing the electromagnets controlling the couplings of the shafts to be driven, said electromagnets being adapted to be energized in authorization permitted angular zones and to be de-energized in predetermined zones arranged between said authorization zones on each side of said defined engagement positions, second means operated once only in each revolution by each driving shaft for energizing the respective electromagnets controlling the couplings of the shafts to be driven after at least one of the driven shafts has been set in rotation only in a synchronization permitted zone extending about a selected common synchronizing engagement point at which the driving shaft operatively engages each shaft to be driven from a rest position.

5. In an addressing machine the combination according to claim 4, in which said first means comprises a first switch and said second means comprises for each driven shaft a second switch and in which the driving shaft effects the closure of the first switch for each defined engagement position of the driving shaft in said authorization zones, and in which each driven shaft eifects the closure of its associated second switch in said synchronization zone which extends beyond the selected common synchronizing engagement point and which when the driven shafts are in angular synchronism extends at least over a part of one of said authorization zones of the driving shaft without overlapping the following authorization zone of the driving shaft, said first and second switches being connected in series with one another and with each electromagnet.

6. In an addressing machine comprising a control mechanism to establish drive connection between a rotatable driving part and at least two rotatable driven parts which are required to have synchronized angular rotation, the combination of a positive coupling for each driven part, each coupling making drive connection with the driving part only in defined angular positions of the 8 driving part, and electrical means for each coupling governed by the angular position of the driven parts in rotation to render each coupling operative when driven parts already in rotation are in a predetermined angular position relative to one of the defined positions of the driving part.

7. In an addressing machine comprising a control mechanism to establish drive connection between a rotatable driving part and at least two rotatable driven parts which are required to have synchronized angular rotation, the combination of a positive coupling for each driven part, each coupling being arranged for drive connection with the driving part only in defined angular positions of the driving part, electromagnets to control each coupling part, circuits connected to energize the electromagnets, switch means operated by each driven part to close the circuit of each electromagnet through a synchronization zone which extends beyond a selected common synchronizing engagement point of the associated driven parts and switch means operated by the driving part in authorization zones corresponding to said defined angular positions to complete said circuits when said driving part reaches a position corresponding to the first encountered authorization zone with all the driven parts at rest, and when said driving part reaches the same authorization zone if a driven part has already been set in rotation and means to initiate at will the driving of one of said driven parts prior to the driving of the other driven parts.

8. In a control mechanism to establish drive connection between a rotatable driving part and at least two rotatable driven parts which are required to have synchronized angular rotation, the combination of a drive coupling for each driven part, each coupling being arranged for drive connection with the driving part only in defined angular positions of the driving part, electromagnets to control each coupling part, circuits connected for selective energization of the electromagnets, a switch for opening and closing each circuit of each electromagnet, a cam driven by each driven part and formed to close the switch once each revolution in a zone extending about a selected common point for engagement of the associated driven parts, and another switch to complete each circuit, and a cam driven by the driving part to close said other switch in zones correspondingto said defined angular positions of the driving part.

9. In a control mechanism to establish drive connection between a rotatable driving part and at least two rotatable driven parts which are required to have a fixed relative angular position, the combination of a drive coupling for each driven part, each coupling making drive connection with the driving part only in defined angular positions of the driving part, electrical means for each coupling governed by the angular position of the driven parts to render each coupling operative when the driven parts are in a predetermined angular position relative to one of the defined positions of the driving part, and means to render each drive coupling inoperative in each rotation of the driven part.

10. In a control mechanism to establish drive connection between a rotatable driving part and at least two rotatable driven parts which are required to have a fixed relative angular position, the combination of a drive coupling for each driven part, each coupling comprising a component movable on its driven part between coupling and non-coupling position, a holding member to hold the coupling component in non-coupling position, an electromagnet to render the holding member inoperative to release the coupling member for coupling engagement with the driving member in one of its defined angular positions, and switches controlled by the driven parts and by the driving part to energize the electromagnets in zones extending about a theoretical point of engagement of the driven parts and corresponding to the defined angular positions of the driving part.

11. In a control mechanism to establish drive connection between a rotatable driving part and at least two rotatable driven parts which are required to have a fixed relative angular position, the combination of a drive coupling for each driven part, each coupling comprising a component movable on its driven part between coupling and non-coupling position, a holding member to hold the coupling component in non-coupling position, an electromagnet to render the holding member inoperative to release the coupling member for coupling engagement with the driving part in one of its defined angular positions, switches controlled by the driven parts and by the driving part to energize the electromagnets in zones extending about the theoretical point of engagement of the driven parts and corresponding to the defined angular positions of the driving part, and means operated in each rotation of a driven part to re-set the holding member.

12. In an addressing machine having a driving shaft and at least two driven shafts to be rotated in angular synchronization, the driving shaft having defined drive engagement positions at which driven shafts are operatively engaged by it, a drive control mechanism comprising a coupling for each driven shaft the coupling being such as to make coupling engagement between the driving shaft and its driven shaft only at one of the defined positions of the driving shaft, an electromagnet controlling the operation of each coupling, and means operated by each driven shaft for controlling each electromagnet as to allow coupling engagement to be made in a synchronization zone extending beyond a selected common synchronizing engagement point of the shafts to be driven for each defined coupling position of the driving shaft, the coupling engagement being effected for each of the shafts to be driven from a rest position at the same defined engagement position of the driving shaft as for driven shafts already in rotation and means for initiating at will the driving of some of the driven shafts ahead of the other driven shafts.

13. In an addressing machine according to claim 4 further comprising operator-controlled selector means related respectively to the driven shafts and an operatorcontrolled component to render active the coupling of one among the shafts to be driven in accordance with the selection of the selector means.

References Cited in the file of this patent UNITED STATES PATENTS 1,637,161 Richard July 26,1927 2,380,542 Nolde July 31, 1945 2,406,040 Ryan Aug. 20, 1946 2,616,363 Ostwaldt Nov. 4, 1952 2,683,514 Hardway July 13, 1954 2,732,793 Gollwitzer Jan. 31, 1956 

